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Replace A/C Compressor??

I have a circa 1992 Carrier A/C residential A/C system Model 38TKB042310 that has been giving us some trouble over the past few years, but this year the tech says it needs a new compressor.

2 years ago, the evaporator was freezing up and the system was low on refrigerant. He added some and the system worked fine for the rest of the year. Tech also replaced the cap on one of the schrader valves.

Last year the evaporator was freezing up and the system was low on refrigerant. He added some and the system worked fine for the rest of the year.

This year we decided to be pro-active and we called the tech out before the evaporator had a chance to freeze up expecting for him to add refrigerant. However, he told us that they must have fixed the leak and the system was overcharged and he removed refrigerant. After he performed the work, my wife said that the compressor was so loud that she couldn't hardly talk to a friend inside the house. This lasted about 30minutes or so. We called for a tech to come back out to look at it, but by that time the system was working properly again. The system worked properly for about a 3 weeks afterwards.

We went on vacation (set the Tstat to 84 degrees). When we returned home, I turned the temp down on the Tstat, but the compressor didn't turn on. The condensor fan is running, but the compressor usually won't turn on. If I let the system sit, the compressor will turn on and usually runs for 5-10minutes and then shuts off (fan continues to run). It is not cooling when the compressor runs (high pressure side seems to get warm, but low pressure side is not cold at all).

The service tech says that the compressor needs to be replaced because it's tripping the overload protection. He says that it's pulling 38A (on a 40A circuit). He stated that the motor could have been damaged if there was a power surge when the compressor was turning on (while we were gone). If this were the case, I would think that the system would cool when the compressor was running. He also said that there could be internal damage to the compressor. This seems more likely to me.

Sorry for the long story, but I thought the details and history would help. Does anyone have thoughts on this? I'd rather not replace this if it's not necessary. Also, any chance that removing some refrigerant this year put the system in a situation that could damage the compressor? Should I get a second opinion?

Even though money is tight. You'll be better off with a new system. Your system probably still has a leak. And a new compresor willonly have a 1 year warranty.
A new system will have a much longer warranty.